The French love using fruits in their desserts. Whether it’s fresh fruit topped on a custard or a cake with baked fruit in it, like this plum tatin, they’re big fans of incorporating fruit into dessert. The word tatin represents an upside down cake, which is exactly what this plum tatin is. Rather than have a cake (or sometimes a shortbread crust) on the bottom with fruit placed on top, this plum tatin has the plums on the bottom of the pan with the cake sitting on top. The thinking behind this method is that when you flip the tatin out of the pan, all the plum juices sink down into the cake and you get a deliciously sweet and moist cake full of plum juices. The method is simple and the result is an incredibly delectable dessert.
The only tricky part of making this cake is getting the caramelized sugar right. The caramelized sugar gets poured over the halved plums that sit on the bottom of your pan. This helps sweeten the fruit and act as a sort of adhesive to help the plums stay in place once the cake is flipped over. Caramelizing sugar just requires a little water and sugar over high heat. The trick is not to take your eyes off the heated sugar for even a second, and to remove the sugar from the heat as soon as it turns a warm amber color. If you wait too long, it can very easily burn. Once you get this part down, the rest of this recipe is a piece of cake (no pun intended!), and totally worth the careful attention. Please just take care to read the recipe notes at the bottom!